Hurricane Sandy: Questions answered
Meteorologist Paul Gross answers questions about hurricane Sandy
I'm receiving a lot of questions about Hurricane Sandy, so here's what you need to know:
Q: It's almost November ... I thought we didn't get hurricanes this late in the season.
A: While the peak of hurricane season is indeed in August and September, tropical weather systems occasionally do develop this late. In fact, in 2005 there were four storms later than this!
Q: "Sandy" is near the end of the alphabet for hurricane names. What happens if we run out of letters?
A: Great question, and we actually already had our "T" storm...Tropical Storm Tony, which was in the central Atlantic and didn't cause any trouble. That means we only have Valerie and William left on the list for this year. If we reach the end of the alphabet, then we do what we did back in 2005: name any additional storms using the Greek alphabet, when we had storms named Alpha, Beta, Gamma, Delta, Epsilon, and Zeta!
Q: Why did Sandy remain so strong through landfall?
A: There are two main factors that determine the strength of a tropical weather system: sea-surface temperature, and wind aloft. As long as ocean surface temps are above 82 degrees, and as long as winds aloft remain light (i.e., little wind shear), then tropical weather systems can flourish.
However, a third factor came into play with Sandy: a strong upper level trough of low pressure (and its accompanying cold air) that is just now starting to interact with Sandy, and will quickly transition it from a tropical system to a "regular" storm system similar to those big winter storms we get. So even though Sandy will weaken after she makes landfall, this transition will maintain its status as a very strong storm system for at least the next day or two.
Q: Why is storm surge such a big deal with this particular storm?
A: Because we have a full moon tomorrow, which means that high tide is much higher than normal. So, those strong onshore winds blowing ocean water inland start with an already higher than normal water level when it's high tide.
Q: Is global warming causing more hurricanes?
A: Climate scientists that I've recently spoken to say that global warming probably will not cause more hurricanes, but the warming ocean temperatures likely will create stronger hurricanes. So, there may be fewer but stronger hurricanes in our warmer world. There is a lot of ongoing research in this area.